panic, but /var/crash ist empty

[Helmut Schneider]

Brandon Gooch wrote:

> On Wed, Apr 27, 2011 at 1:44 PM, Helmut Schneider <jumper99 at gmx.de>
> wrote:
> > What can I do to create a backtrace to open a PR?
> 
> To get a backtrace from the crash (or drop to the debugger), you'll
> need to compile a kernel with at least a couple of options defined.
> These two:
> 
> options KDB
> options DDB
> 
> ...will allow you to work with the debugger on the console after a
> crash.
> 
> Further, with the option KDB_TRACE in the kernel config, you'll get a
> backtrace printed automatically when the kernel panicsb.
> 
> Here are a couple of excellent documents to read to get you started:
> 
>
http://www.freebsd.org/doc/en/books/handbook/kernelconfig-building.html
>
http://www.freebsd.org/doc/en/books/developers-handbook/kerneldebug.html
> 
> Kernel debug options:
> 
>
http://www.freebsd.org/doc/en/books/developers-handbook/kerneldebug-options.html

Thanks for the links, I meanwhile was able to create the bt and the PR:

http://www.freebsd.org/cgi/query-pr.cgi?pr=156691

Helmut